Notes payable gross.

No definition available.

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- Definition

The carrying value, as of the date of each statement of financial position presented, of real estate which is owned and pledged as collateral for related debt obligation

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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- Definition

The aggregate amount of the participation liability at the end of the accounting period.

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- Definition

The cash inflow from a borrowing supported by a written promise to pay an obligation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Mortgages Payable - Additional Information (Detail) - USD ($) $ in Thousands			12 Months Ended
	Sep. 14, 2020	Feb. 14, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 23, 2020	Sep. 13, 2020
Mortgage Loans on Real Estate
Repayments of long-term debt			$ 50,000	$ 0	$ 160,142
Net carrying value of real estate collateralizing the debt			657,800
Mortgages
Mortgage Loans on Real Estate
Notes payable, gross			1,164,544	974,836
Rego Park II \| Retail space \| Mortgages
Mortgage Loans on Real Estate
Loan participation balance		$ 50,000
Proceeds from loan participation		$ 145,000
Notes payable, gross			$ 202,544	56,836
Interest rate			1.50%
Debt instrument, description of variable rate basis			LIBOR
Rego Park II \| Retail space \| Mortgages \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR			1.35%
731 Lexington Avenue \| Retail space
Mortgage Loans on Real Estate
Repayments of long-term debt	$ 50,000
731 Lexington Avenue \| Retail space \| Mortgages
Mortgage Loans on Real Estate
Notes payable, gross	$ 300,000		$ 300,000	350,000			$ 350,000
Basis spread over LIBOR	1.40%
Interest rate			1.55%
731 Lexington Avenue \| Retail space \| Mortgages \| Interest Rate Swap
Mortgage Loans on Real Estate
Interest rate			1.72%
Debt instrument, description of variable rate basis			LIBOR
731 Lexington Avenue \| Retail space \| Mortgages \| LIBOR \| Interest Rate Swap
Mortgage Loans on Real Estate
Basis spread over LIBOR			1.40%
731 Lexington Avenue \| Office space \| Mortgages
Mortgage Loans on Real Estate
Notes payable, gross			$ 500,000	500,000
Interest rate			1.06%
Debt instrument, description of variable rate basis			LIBOR
731 Lexington Avenue \| Office space \| Mortgages \| LIBOR
Mortgage Loans on Real Estate
Basis spread over LIBOR			0.90%
The Alexander \| Residence space \| Mortgages
Mortgage Loans on Real Estate
Notes payable, gross						$ 94,000
Interest rate						2.63%
Participation Agreement \| Rego Park II
Mortgage Loans on Real Estate
Loan participation balance			$ 50,000	$ 195,708